This invention relates to folding knives, and in particular to a bolster-actuated lockback knife. A knife in this category employs means for locking one or more blades in an extended position for improved safety.
Foldable lockback knives have been used for many years and many designs have been proposed for accomplishing positive locking and ease of locking and unlocking. Some of these designs are generally satisfactory when the knives are new or have been kept clean. However, others have various sharp edges which catch on clothing or may cut the hands in use, and many do not have a neat uncluttered appearance such as that of a conventional non-locking pocket knife.
A principal defect or disadvantage of many prior art designs is that the operating parts of the locking mechanisms are exposed. Such knives are used primarily by campers, hunters and fishermen, and sand, wood chips, and other debris quickly work in between the parts, including the spring components, and interfere with proper operation. The gaps are frequently small and inaccessible so that it is extremely difficult to clean them.
The exposed parts in many designs project from the knife handle, and thus are susceptible to false operation occasioned by even routine manual handling.
Prior art patents disclosing knife locks are as follows: U.S. Pat. Nos. 292,473, 690,927, 801,970, 866,431, 915,269, 988,068, 1,030,058, 1,169,000, 1,262,390, 1,264,625, 1,265,723, 1,451,607, 1,498,517, 2,596,294, 2,896,576, 3,942,249 and 4,040,181.